yarn 3.2源码分析之ResourceManager

概述

ResourceManager是一系列组件的集合。它会加载core-site.xml和yarn-site.xml，同时创建yarn scheduler、RMAppManager等一系列组件。

创建yarn scheduler

获取yarn.resourcemanager.scheduler.class配置项，默认是CapacityScheduler 

 public static final String RM_SCHEDULER = "yarn.resourcemanager.scheduler.class";
    public static final String DEFAULT_RM_SCHEDULER = "org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler"; 

 protected ResourceScheduler createScheduler() {
    //获取yarn.resourcemanager.scheduler.class配置项，默认是CapacityScheduler 
    String schedulerClassName = conf.get(YarnConfiguration.RM_SCHEDULER,
        YarnConfiguration.DEFAULT_RM_SCHEDULER);
    LOG.info("Using Scheduler: " + schedulerClassName);
    try {
      Class<?> schedulerClazz = Class.forName(schedulerClassName);
      if (ResourceScheduler.class.isAssignableFrom(schedulerClazz)) {
        return (ResourceScheduler) ReflectionUtils.newInstance(schedulerClazz,
            this.conf);
      } else {
        throw new YarnRuntimeException("Class: " + schedulerClassName
            + " not instance of " + ResourceScheduler.class.getCanonicalName());
      }
    } catch (ClassNotFoundException e) {
      throw new YarnRuntimeException("Could not instantiate Scheduler: "
          + schedulerClassName, e);
    }
  }

Application管理模块

protected RMAppManager createRMAppManager() {
    return new RMAppManager(this.rmContext, this.scheduler, this.masterService,
      this.applicationACLsManager, this.conf);
  }

 

ApplicationMaster管理模块

创建ApplicationMasterService

protected ApplicationMasterService createApplicationMasterService() {
    Configuration config = this.rmContext.getYarnConfiguration();
    if (isOpportunisticSchedulingEnabled(conf)) {
      if (YarnConfiguration.isDistSchedulingEnabled(config) &&
          !YarnConfiguration
              .isOpportunisticContainerAllocationEnabled(config)) {
        throw new YarnRuntimeException(
            "Invalid parameters: opportunistic container allocation has to " +
                "be enabled when distributed scheduling is enabled.");
      }
      OpportunisticContainerAllocatorAMService
          oppContainerAllocatingAMService =
          new OpportunisticContainerAllocatorAMService(this.rmContext,
              scheduler);
      this.rmContext.setContainerQueueLimitCalculator(
          oppContainerAllocatingAMService.getNodeManagerQueueLimitCalculator());
      return oppContainerAllocatingAMService;
    }
    return new ApplicationMasterService(this.rmContext, scheduler);
  }

ApplicationMasterLauncher

protected ApplicationMasterLauncher createAMLauncher() {
    return new ApplicationMasterLauncher(this.rmContext);
  }

NodeManager管理模块

protected ResourceTrackerService createResourceTrackerService() {
    return new ResourceTrackerService(this.rmContext, this.nodesListManager,
        this.nmLivelinessMonitor,
        this.rmContext.getContainerTokenSecretManager(),
        this.rmContext.getNMTokenSecretManager());
  }

用户管理模块

创建AdminService

 protected AdminService createAdminService() {
    return new AdminService(this);
  }

创建ClientRMService

protected ClientRMService createClientRMService() {
    return new ClientRMService(this.rmContext, scheduler, this.rmAppManager,
        this.applicationACLsManager, this.queueACLsManager,
        this.rmContext.getRMDelegationTokenSecretManager());
  }

ResourceManager的交互协议

• ResourceTracker

    NodeManager通过该协议向ResourceManager中注册、汇报节点健康情况以及Container的运行状态，并且领取ResourceManager下达的重新初始化、清理Container等命令。NodeManager和ResourceManager这种RPC通信采用了和MRv1类似的“pull模型”（ResourceManager充当RPC server角色，NodeManager充当RPC client角色），NodeManager周期性主动地向ResourceManager发起请求，并且领取下达给自己的命令。

• ApplicationMasterProtocol

  应用程序的ApplicationMaster同过该协议向ResourceManager注册、申请和释放资源。该协议和上面协议同样也是采用了“pull模型”，其中在RPC机制中，ApplicationMaster充当RPC client角色，ResourceManager充当RPC server角色。

• ApplicationClientProtocol

• 客户端通过该协议向ResourceManager提交应用程序、控制应用程序（如杀死job）以及查询应用程序的运行状态等。在该RPC 协议中应用程序客户端充当RPC client角色，ResourceManager充当RPC server角色。

整理一下ResourceManager与NodeManager、ApplicationMaster和客户端RPC协议交互的信息：

上图中的ResourceTrackeServer、ApplicationMasterService 、ClientRMServer是ResourceManager中处理上述功能的组件。

参考：Yarn之ResourceManager详细分析